1. Field of the Invention
The invention is directed to a method for creating and outputting at least one print page. At least one print page that contains a plurality of blocks is created with the assistance of a first program module. Each block contains first image data of picture elements. An output unit outputs picture elements, whose image properties are determined by output parameters, on the basis of second image data. The output unit outputs the print page with the image data adapted to the output parameters. The invention is also directed to a computer program as well as to a system for implementing the method.
2. Description of the Related Art
In data processing systems, image data of print pages are output on output units, for example, on picture screen and on printers. The print pages are created with the assistance of a first program module (e.g., with a text processing program) with a forms editor or with a desk top publishing (DTP) program module. These image data must be converted for outputting the image data so that the respective output unit can process these data. This conversion is implemented, for example, with the assistance of a printer driver program module given output of the print page by a printer or with the assistance of a picture screen driver program module given output of the print page on a display unit. Printer driver and picture screen driver program modules are also referred to as “drive program modules”.
A respective printer driver program module is present for different printers having different output parameters as well as for different printer types. The output parameters of the printer can be pre-set for all print pages to be printed in the printer driver program module, preferably in forms of the printer driver, what are referred to as “register cards” of the printer driver. Standard parameters such as the contrast, the brightness, a reduction of the possible output resolution of the printer, the paper feed, the desired color mixing and the desired printing density can thereby be pre-set. Depending on the printer type, settings for activating duplex printing methods, for activating color printing as well as for color matching are also possible.
When creating the print pages in the first program module, pre-existing blocks that contain image data of picture elements are inserted and arranged. Given inserted blocks, particularly given inserted pictures and graphics, the image parameters of the blocks differ, particularly in terms of the image parameters of resolution and color depth, from the output parameters of a printer on which the blocks are output together with further blocks of the print page. The specific printer on which the print pages will be output has often not been determined when creating the print pages since the output of the print pages often does not ensue immediately after the creation of the print page but at a much later time and with the assistance of a further data processing system. As a consequence of the different output parameters of the available printers on which the print page can be output, the output parameters have often not been determined when the print page is created. The image parameters of the blocks can therefore not be adapted at this time to the output parameters of the printer when the print page is created.
The blocks usually have image parameters that the available printers are often incapable of presenting. Thus, for example, standard resolutions of pictures and graphics in image production and in image processing are 1200 through 9600 dots per inch (dpi). Color depths between 8 and 24 bits are standard. A color depth of 8 bits means that, for example, a dot can be presented in 256 different colors or in 256 different gray scales. Typical printers, however, usually have a resolution of only 150 through 600 dpi given a color depth of 1 through 8 bits. For printers that can only output one color, for example black, such printers must convert the colors into gray scales and, potentially, convert the gray scales into a black-and-white graphics with the assistance of a rastering process, and in addition must reduce the resolution. A color allocation must be made given multi-color (e.g., two-color) printing.
The information contained in the image data of the blocks are reduced in the reduction of the resolution and in a necessary color conversion. It is therefore also not meaningful to uniformly modify the image data of the blocks to, for example, 600 dpi and to a color depth of 8 bits when creating the print page. If, namely, the printer can only output a resolution of 300 dpi, then the image data of all blocks must be converted again. For example, in this situation, the image data of a graphics with a resolution of 1200 dpi are converted into image data of a graphics with a resolution of 600 dpi; for output on the printer, image data of a graphics with 300 dpi must be generated. Two conversion events of the 1200 dpi graphics are thus needed. Information is lost in every conversion. When converting the graphic from 600 dpi to 300 dpi, all information that are contained in the original 1200 dpi graphic are no longer available. A graphic with 300 dpi that has been produced from the graphic with 1200 dpi using two conversion steps is qualitatively poorer than a graphic with 300 dpi that has been produced from the image data of the graphic with 1200 dpi in a single conversion step during the conversion.
In some blocks, references to image data in data sources are inserted into the print page instead of the image data when creating the print page. The image data of the blocks specified by the references are then read in from the data sources shortly before the printout and are adapted to the output parameters of the output unit together with further image data and are output.
The print page that has been created can be output at different output units that make variously strict demands of the quality of the image data. In order to avoid a high information loss, the image data must be made available with high quality. Accordingly, it is not expedient—as in the Prior Art—to already make the image parameters of these print data uniform when creating the print pages and/or to adapt them to the output parameters of the output unit. The current data with the image parameters with which they are available in the data source are added to the further image data of the print page shortly before the printout.
U.S. Pat. No. 5,398,289 discloses a method and a system in which a document generated by an operator with the assistance of a program module is output object optimized. Object-oriented reproduction instructions for specifying the object can be generated by the operator when drafting the document or can be automatically generated. An output device makes reproduction and compression techniques for the object-oriented output available using specific hardware and software modules. The respective object is processed in the output unit on the basis of the reproduction instructions with the assistance of reproduction and compression techniques before being output.